IRD

The climate of West Africa is subject to some of the most variable rainfall patterns observed anywhere in the world. In the past, the region has suffered several decades of severe droughts, whilst more recently major flood events have struck a number of the region's rapidly expanding cities. The consequences of these climatic extremes for the population have been particularly pronounced due to widespread and severe poverty. Global climate change, coming on top of such a variable and unpredictable regional climate, poses a major threat to the populations and economies of West Africa. Although the pathway from climate change to human suffering in West Africa is very short, there are some key bottlenecks to using climate projections to mitigate against risks to the population. Critical gaps exist in knowledge of how West African climate will change over the course of the 21st century, and the uncertainties make it almost impossible for agencies to deliver well-informed plans for the coming decades in critical areas such as food security, urban development and water. Even with the best climate information, it remains a significant challenge to integrate the scientific knowledge into planning and management structures. This collaborative project between scientists and policy makers in West Africa and Europe will, on the one hand, increase understanding of the regional climate and how it will change, and on the other, apply that knowledge to practical development questions. One of the key challenges for climate science is to understand how the changing composition of the atmosphere (notably CO2) will impact on the frequency and intensity of extreme events such as floods and droughts. In West Africa, these events are tied to the behaviour of convective rain storms; when storms are particularly intense or occur in rapid succession, devastating floods may result, whilst a week or two without storms during the wet season can trigger crop failure. Climate scientists rely on computer simulations of the global atmosphere, oceans and continents, yet these models have a very crude description of convective storms. For the first time, a new generation of regional climate models is emerging which realistically depict storms, and critically, how storms respond to factors such as land and ocean conditions, and increases in CO2. AMMA-2050 will use these new computer simulations alongside conventional climate models and historical observations, to understand why the statistics of key climate extremes are changing, and what this tells us about climate and its extremes in future decades. The outputs from the models will be used to examine impacts on key sectors in West African society, notably water and agriculture. Adaptation options will be explored, for example through the use of alternative crops, taking account of the inherent uncertainties in climate information, and the ways in which it is interpreted by decision-makers. We will focus on two questions. Firstly, in Senegal we will identify sustainable agricultural adaptation strategies and the policy frameworks to support those options. Secondly, we will examine how climate changes are likely to affect flooding in the rapidly growing city of Ouagadougou in Burkina Faso. The research and capacity building work of AMMA-2050 will help develop a new generation of African researchers and decision-makers, well-placed to respond to the requirements of West African nations. Within AMMA-2050, end-users have an important role, and their needs are embedded in project design and delivery, such that outputs will be responsive to their needs, and delivered in a format that is easily used. Enhanced resilience is an important aim of the project: it starts with improving our understanding of the climate signal over West Africa and leads through to decisions being made in specific pilot studies that showcase the importance of using improved and impact-sensitive science outputs.

Loiasis, an infectious disease caused by the parasitic worm Loa loa, affects more than 15 million individuals in central Africa, and more than 100 million people are potentially exposed to infection. Since its first description in 1770, the international scientific community has considered this filarial disease as benign. I recently demonstrated that loiasis significantly reduces the life expectancy of infected people. I aim to definitively shift the prevailing paradigm of “benign loiasis” by showing that it can induce severe complications in various organs. I will conduct the first population-wide evaluation of morbidity in rural areas of Central Africa by performing systematic examinations on 4,900 selected individuals. This sample size will enable accurate estimation of prevalences of cardiovascular and renal diseases and of functional asplenia. Our results may lead to the recognition of loiasis as a significant public health problem. Such recognition could motivate integration of loiasis into the WHO’s list of Neglected Tropical Diseases. In addition, should loiasis be found to induce a functional asplenia, combating this disease could have a huge impact on the incidence and severity of other severe and common infections favoured by asplenia, such as malaria and pneumonia. Incidentally, specific recommendations regarding pneumococcal vaccination in loiasis-endemic areas could be made. Another possible consequence of our findings is changes in the management of people identified as having high levels of Loa loa infection during routine surveys or onchocerciasis elimination activities. Presently, these people are excluded from ivermectin treatment (because of the risk of post-treatment encephalopathy), and little is done to lower their level of infection. Confirmation that loiasis can cause serious complications would motivate an ethical obligation to develop strategies to manage these cases in order to lower their burden of the disease.

Phenotypes are largely determined by genetic factors. However, a given genotype can give rise to very distinct phenotypes, as exemplified by the diversity of cell types in multicellular organisms. This phenotypic plasticity results from epigenetic changes; that is, reversible modifications to the DNA molecule and its associated proteins that modulate gene expression patterns. Epigenetic changes are critical to the establishment of developmental programs, but also to adjust transcription in response to the environment. The latter is particularly important for plant adaptation: owing to a sessile (immobile) lifestyle, plants cannot run away from adversity, and thus adapt to their environment by tuning gene expression in response to changing conditions. Most epigenetic information is erased from one generation to the next, so that new organisms start their life cycle with a “fresh” potential. However, there are instances in nature of heritable epigenetic marks that can be transmitted to the next generation. Thus, owing to their role in shaping gene expression, and the potential for heritable changes, epigenetic factors are of great interest for plant breeders, in their quest for adaptable, high yielding phenotypes. Most of our current understanding of epigenetic processes in plants has been developed in Arabidopsis, a key model system. However, the Arabidopsis epigenome is rather idiosyncratic, and this knowledge might translate poorly to crops. Here, we will use an interdisciplinary approach combining original genetic materials and bioinformatics to analyze epigenetic regulatory pathways in maize, with a focus on reproductive development. Maize is an important model plant, with a large and dynamic epigenome much more typical of crops. It is also a crop of great economic importance. Better understanding the epigenome of maize will open the door to the manipulation of key agronomic traits, including reproductive development, which is under strong epigenetic influence.

The climate of West Africa is subject to some of the most variable rainfall patterns observed anywhere in the world. In the past, the region has suffered several decades of severe droughts, whilst more recently major flood events have struck a number of the region's rapidly expanding cities. The consequences of these climatic extremes for the population have been particularly pronounced due to widespread and severe poverty. Global climate change, coming on top of such a variable and unpredictable regional climate, poses a major threat to the populations and economies of West Africa. Although the pathway from climate change to human suffering in West Africa is very short, there are some key bottlenecks to using climate projections to mitigate against risks to the population. Critical gaps exist in knowledge of how West African climate will change over the course of the 21st century, and the uncertainties make it almost impossible for agencies to deliver well-informed plans for the coming decades in critical areas such as food security, urban development and water. Even with the best climate information, it remains a significant challenge to integrate the scientific knowledge into planning and management structures. This collaborative project between scientists and policy makers in West Africa and Europe will, on the one hand, increase understanding of the regional climate and how it will change, and on the other, apply that knowledge to practical development questions. One of the key challenges for climate science is to understand how the changing composition of the atmosphere (notably CO2) will impact on the frequency and intensity of extreme events such as floods and droughts. In West Africa, these events are tied to the behaviour of convective rain storms; when storms are particularly intense or occur in rapid succession, devastating floods may result, whilst a week or two without storms during the wet season can trigger crop failure. Climate scientists rely on computer simulations of the global atmosphere, oceans and continents, yet these models have a very crude description of convective storms. For the first time, a new generation of regional climate models is emerging which realistically depict storms, and critically, how storms respond to factors such as land and ocean conditions, and increases in CO2. AMMA-2050 will use these new computer simulations alongside conventional climate models and historical observations, to understand why the statistics of key climate extremes are changing, and what this tells us about climate and its extremes in future decades. The outputs from the models will be used to examine impacts on key sectors in West African society, notably water and agriculture. Adaptation options will be explored, for example through the use of alternative crops, taking account of the inherent uncertainties in climate information, and the ways in which it is interpreted by decision-makers. We will focus on two questions. Firstly, in Senegal we will identify sustainable agricultural adaptation strategies and the policy frameworks to support those options. Secondly, we will examine how climate changes are likely to affect flooding in the rapidly growing city of Ouagadougou in Burkina Faso. The research and capacity building work of AMMA-2050 will help develop a new generation of African researchers and decision-makers, well-placed to respond to the requirements of West African nations. Within AMMA-2050, end-users have an important role, and their needs are embedded in project design and delivery, such that outputs will be responsive to their needs, and delivered in a format that is easily used. Enhanced resilience is an important aim of the project: it starts with improving our understanding of the climate signal over West Africa and leads through to decisions being made in specific pilot studies that showcase the importance of using improved and impact-sensitive science outputs.